Questions tagged [electricity]
The study of the presence and flow of electric charge. Charges, currents, fields, potentials.
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Why is current through the short circuited wire not zero? [duplicate]
Why does current flow in a short circuited wire? I understand that it offers negligible resistance to the flow of charges, but two points on the short circuited wire will have the same potential, so ...
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If there's magnetic field around current-carrying wire, why doesn't it always exist?
Motion is relative.
If we say train is moving, it moves with respect to the Earth. If we are inside, it doesn't move from our point of view.
Then, with respect to what object do we say that electrons ...
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How much energy does a single lightning bolt from this Van De Graaff generator consume?
I recently visited the Boston Museum of Science and saw a show using their "world's largest air-insulated Van de Graaff generator." I was curious as to the actual energy output of the ...
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Anode/cathode in an electrolytic capacitor during discharge?
Wikipedia says "an electrolytic capacitor is a capacitor whose anode or positive plate is made of a metal that forms an insulating oxide layer" (1, link). Elsewhere, wikipedia seems to ...
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Heating a Material with Negative temperature coefficient of resistance
TCR (Temperature Coefficient of Resistance): $R = R_0[1 + α(T - T₀)]$ Where: $R$ is the resistance at temperature $T$, $R_0$ is the resistance at a reference temperature $T_0$, $\alpha$ is the TCR of ...
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I don't understand how current always chooses the path of least resistance [duplicate]
As the question states, I don't understand how Current always chooses the path of least resistance.
How does it even "know" to pick that path
For example, if we have a short circuit which ...
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Modeling an Electrolyzer System
In this study, the authors provide an equation for operating cell voltage: $V_{cell} = V_{rev} + V_{act} + V_{ohm}$, the sum of the reversible overvoltage, the activation overvoltage and the ohmic ...
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Why do charges exist in the first place?
Why do charges exist, how did they come into existence? (if any theories exist, then please explain them in somewhat detail)
What would happen if charges never existed?
Please explain the answers at ...
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How is electrostatic force 'lost' during conduction in these examples?
When you rub a glass rod against silk cloth, the glass rod becomes positively charged and the cloth becomes negatively charged. So they now can attract each other.
However, after this 'attraction' ...
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Why doesn't charge accumulate in a loop?
When learning about electromagnetism at my university, electricity flow is generally shown as a conductor with a high potential at one end and a low potential at the other and thus charges flowing ...
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Trouble understanding an example in electricity and magnetism by M.Purcell
I'm having trouble understating the following example in section 3.2 of electricity and magnetism by M.Purcell:
In paragraph 2 of the solution, it states that "The combination of these charges ...
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Why are the formulae for the electric flux density and the magnetic flux density fundamentally different?
I've been delving a bit beyond just using what's typically given as the "electric field" and "magnetic field" in various problems, and finding out about the various more ...
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What happens to the charge which enters the positive terminal of the battery in a circuit? [duplicate]
SO basically , I know that a battery creates potential difference or V in a circuit to flow, by doing work on the charge(electrons) . The motion of the charge(electrons) is from the -ve or negative ...
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Is electric current actually the flow of electrical charge?
In my high school, the definition of electrical current is "the flow of charges" but I have seen a video about how electricity actually works and it seems to me that electrical current is ...
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Would this simple design function as an electromagnet?
I was thinking about electromagnets today and a thought popped up in my mind on what would be a very simple way to create an electromagnet.
Although I have not built and tested it, I am pretty sure ...
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